Tara’s grandmother is 70 years old and has a passion for embroidery. She faces difficulty in threading the needle as the eye of the needle appears blurred. The ophthalmologist diagnosed it as an age-related disorder.
Where is the image formed in the above disorder?
Topic: Image position in long-sightedness
Answer
BEHIND THE RETINA.
Because the hardened lens cannot bulge enough, the light rays from a near object are not converged sufficiently and would come to a focus at a point BEYOND the retina. What actually lands on the retina is a blurred circle rather than a sharp point.
THE LOGIC that lets you work this out rather than memorise it: too LITTLE bending means the focus is too FAR back — behind the retina. Too MUCH bending means the focus is too far forward — in front of the retina, which is myopia.
Once you know where the image falls, the correcting lens follows automatically: behind the retina needs a convex lens to bring the focus forward.